@urbankitstudio/atlas

JS SDK for the UrbanKit County Parcel REST API Atlas — a curated index of public ArcGIS REST endpoints for US county parcel data, with searchable field metadata, sample queries, and license info.

Use it to:

• Look up the parcel REST endpoint for a given US county (e.g. Kane County, IL).
• Discover which fields are searchable on each endpoint (PIN, owner name, address).
• Build deep-links into the UrbanKit parcel lookup tool.

The data is the same set powering urbankitstudio.com/parcel-atlas, bundled offline so your code does not need to make a runtime network request.

Install

npm i @urbankitstudio/atlas

Works in Node.js (>=18) and modern bundlers (Vite, webpack, esbuild, Rollup, Next.js, Remix). Ships ESM + CJS with full TypeScript types. No runtime dependencies. sideEffects: false.

Quick start

1. List populated states

import { listStates } from "@urbankitstudio/atlas";

const populated = listStates().filter((s) => s.populated);
// [{ slug: "arizona", name: "Arizona", abbrev: "AZ", countyCount: 1, ... }, ...]

2. Look up a county by slug

import { findCounty } from "@urbankitstudio/atlas";

const kane = findCounty("illinois", "kane-county");
if (kane) {
  console.log(kane.endpoints[0].url);
  // → https://gis.kanecountyil.gov/...

  const pin = kane.endpoints[0].searchFields.find((f) => f.name === "PIN");
  console.log(pin?.label);
  // → "Parcel Identification Number (PIN)"
}

3. Look up a county by FIPS code

import { findCountyByFips } from "@urbankitstudio/atlas";

const kane = findCountyByFips("17089"); // 5-digit county FIPS (state + county)
if (kane) {
  console.log(kane.county, kane.stateSlug);
  // → Kane illinois
}
// Unknown, malformed, or non-5-digit input returns undefined (never throws).

4. Build a parcel-lookup deep-link

import { findCounty, buildParcelLookupDeepLink } from "@urbankitstudio/atlas";

const kane = findCounty("illinois", "kane-county")!;
const link = buildParcelLookupDeepLink(kane.endpoints[0]);
// → https://urbankitstudio.com/tools/parcel-lookup?endpoint=https%3A%2F%2F...&fieldHint=TaxName

API

| Function | Returns | |---|---| | listStates() | StateIndexEntry[] — all 50 states + populated flag | | findState(stateSlug) | StateFile \| undefined | | findCounty(stateSlug, countySlug) | CountyRecord \| undefined | | findCountyByFips(fips) | CountyRecord \| undefined — match by 5-digit county FIPS | | listCountiesByState(stateSlug) | CountyRecord[] | | buildParcelLookupDeepLink(endpoint) | URL string into the UrbanKit lookup tool | | slugify(s), countySlugFromName(s) | string helpers matching the atlas slug convention | | statePath(slug), countyPath(state, county) | URL paths under /parcel-atlas |

The full typed root is also exported as atlas:

import { atlas } from "@urbankitstudio/atlas";

atlas.version;          // string
atlas.lastUpdated;      // ISO date
atlas.totals;           // { states, counties, endpoints }
atlas.byStateSlug;      // Map<stateSlug, StateFile>

Coverage today

The atlas currently bundles 155 counties across all 50 US states, covering the largest counties in each. Call listStates() to enumerate the full set; every state is now populated with at least one verified county endpoint.

Counties are added as their public REST endpoints are verified. Package versions bump when data refreshes — pin to a minor range (^0.x) to receive new counties without breaking changes.

The live, browseable atlas lives at urbankitstudio.com/parcel-atlas.

License

MIT — see LICENSE. © 2026 Leo Yong.

This package's atlas dataset (the open discovery layer — county → REST endpoint mappings and field metadata) is provided under MIT. Live, always-fresh and enriched data — geocoding, address→parcel resolution, bulk enrichment, and the data-availability SLA — are the paid UrbanKit Studio API.